textproduct: Quad Cities

KEY MESSAGES

- Extreme Heat Warning continues through this evening for much of the area with ongoing prolonged period of hot and very humid conditions. The humid conditions will continue into the holiday weekend, but cloud cover and rounds of thunderstorms make for great uncertainty if there will be the need for additional heat headlines.

- With the storm track edging closer in from the west/northwest, the local area will be more susceptible to occasional rounds of thunderstorms into the Holiday weekend. Strong to severe storms will be possible, as well as locally heavy rainfall.

SHORT TERM /THROUGH TONIGHT/

Issued at 245 AM CDT Thu Jul 2 2026

Today...Lingering ridge and EML effects will look to keep the brunt of the storm clusters just off to the west and north of the DVN CWA through at least mid afternoon, with the low chance for some southward festering convection to feed down into the far northern CWA toward mid morning. Then with ongoing slow migration and flattening of the southeast CONUS thermal ridge, an embedded MCV moving out of the central plains and along the northwestern flank will look to ignite more thunderstorms along convergent but diffuse boundary acrs west central into northeast IA mid to late this afternoon. There is a lot of uncertainty, but will have to have at least low to moderate CHC POPs to account for some of this activity to battle lingering upper ridge/EML and make it into western and northern portions of the DVN CWA by this evening. Will then have to extend at least 20% POPs south of I-80 later tonight for the chance that any outflow from the storms in the north spills out that far to the south and acts as a focal for isolated to sctrd storms to develop with LLJ convergence on them.

Of course the EML and upper ridge could still win out with the local area not experiencing much storm activity through 12z Friday. After the central into eastern IA storm chances with the MCV this afternoon and evening, another convective spawning ground will look to take place again along the SD/NE border region on eastward along the IA/MN border overnight. There may be a better chance for some of this linear-like MCS to bleed down into at least northern portions of the DVN CWA if even in a decaying fashion. Will have to have POPs to account for all these possibilities in a messy pattern. If mature storms manage to make it into or develop in the local fcst area, they may be capable of damaging winds especially if a cluster develops a cold pool along it's propagation in a high CAPE airmass. Locally heavy rainfall and flash flooding also possible with high PWATs of 1.8+ in place.

As for temps, will let the Excessive Heat Warning ride with ambient temps in the low 90s and low to mid 70 DPTs. With potential storm debris and outflow, only getting heat index readings in the upper 90s north of Hwy 30 and will not re-expand any heat headlines acrs those areas for now.

LONG TERM /FRIDAY THROUGH WEDNESDAY/

Issued at 245 AM CDT Thu Jul 2 2026

Friday...Model ensembles and mid to upper jet progs(which generally do well at this range) show the continued southeast upper ridge de- amplify to allow flattened progressive flow to press acrs the upper Midwest into Saturday. This flow embedded with short waves and MCVs means the adjustment of the main storm track from the north half of the plains through the GRT LKS and on into the northeast CONUS. This will open up the local area for more direct hits by storm clusters as opposed to glancing blows from Friday through at least early Sunday. The oppressive humidity will still be here(aided by crop evapo-transpiration) through the weekend, but convective debris and outflow between the episodes of storms should help reduce the need for additional heat headlines. The heat index may flirt with 100 at a few spots on Friday if we get some hours of insolation breaks, but low confidence on coverage and duration preclude any headline extension or issuance for now. A damaging wind producing MCS may move acrs IA and then effect the local area later Friday night into early Sat morning. Besides an almost daily chance for strong to severe storms through at least Saturday, swaths of heavy rainfall may really add up through Sunday especially acrs the northwest half of IA, southern MN, and into WI.

Longer range progs and upper jet patterns suggest a good bout of ridging to unfold acrs the upper Midwest for a reprieve from the storms by early next week. Temps may be more seasonable and not as hot early next week as well.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 530 AM CDT Thu Jul 2 2026

Generally a VFR TAF fcst with passing high clouds and persistent south to southwesterly sfc wind of 10-15 KTs that may gust to near 20 KTs mid to late this afternoon. But there is the 30-50% chance for a thunderstorms or cluster of storms to develop this afternoon into early evening and move across the area affecting a few TAF sites. It appears that if this happens the sites that appear to have the best chance for at least being in the VCNTY are CID and DBQ. With low confidence on coverage and timing in this atmospheric set up, just went with PROB30s around the more favorable windows for now. If a site were to get impacted by a storm, it may be strong with gusty variable winds and sharply rain-reduced VSBYs as they pass by.

DVN WATCHES/WARNINGS/ADVISORIES

IA...Extreme Heat Warning until 10 PM CDT this evening for IAZ063>068-076>078-087>089-098-099. IL...Extreme Heat Warning until 10 PM CDT this evening for ILZ009- 015>018-024>026-034-035. MO...Extreme Heat Warning until 10 PM CDT this evening for MOZ009- 010.